Mostly spelled incorrectly as “Pozidrive” (including ourselves), Pozidriv (the correct name) is an improved variation on the Phillips drive design.
After the patent for the Phillips head expired, the company GKN Screws and Fasteners created the Pozidriv design.
The Pozidriv drive style was originally formed to address the largest issue Phillips heads are prone to: cam-out. Cam-out is defined as the slipping out of a drive recess that occurs when torque exceeds a certain limit.
The Pozidriv drive style has the same self-centering design of a Phillips drive style but improves upon the two following factors:
Increased torque without cam-out
Greater surface contact engagement between the drive and the recess in the fastener head making it harder to slip when installed correctly